linux-kernel - [RFC PATCH v3 33/35] NTB: epf: Add an additional memory window (MW2) barno mapping on Renesas R-Car

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20251217151609.3162665-34-den@valinux.co.jp>
Date: Thu, 18 Dec 2025 00:16:07 +0900
From: Koichiro Den <den@...inux.co.jp>
To: Frank.Li@....com,
	dave.jiang@...el.com,
	ntb@...ts.linux.dev,
	linux-pci@...r.kernel.org,
	dmaengine@...r.kernel.org,
	linux-renesas-soc@...r.kernel.org,
	netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org
Cc: mani@...nel.org,
	kwilczynski@...nel.org,
	kishon@...nel.org,
	bhelgaas@...gle.com,
	corbet@....net,
	geert+renesas@...der.be,
	magnus.damm@...il.com,
	robh@...nel.org,
	krzk+dt@...nel.org,
	conor+dt@...nel.org,
	vkoul@...nel.org,
	joro@...tes.org,
	will@...nel.org,
	robin.murphy@....com,
	jdmason@...zu.us,
	allenbh@...il.com,
	andrew+netdev@...n.ch,
	davem@...emloft.net,
	edumazet@...gle.com,
	kuba@...nel.org,
	pabeni@...hat.com,
	Basavaraj.Natikar@....com,
	Shyam-sundar.S-k@....com,
	kurt.schwemmer@...rosemi.com,
	logang@...tatee.com,
	jingoohan1@...il.com,
	lpieralisi@...nel.org,
	utkarsh02t@...il.com,
	jbrunet@...libre.com,
	dlemoal@...nel.org,
	arnd@...db.de,
	elfring@...rs.sourceforge.net,
	den@...inux.co.jp
Subject: [RFC PATCH v3 33/35] NTB: epf: Add an additional memory window (MW2) barno mapping on Renesas R-Car

To enable remote eDMA mode on NTB transport, one additional memory
window is required. Since a single BAR can now be split into multiple
memory windows, add MW2 to BAR2 on R-Car.

For pci_epf_vntb configfs settings, users who want to use MW2 (e.g. to
enable remote eDMA mode for NTB transport as mentioned above) may
configure as follows:

  $ echo 2       > functions/pci_epf_vntb/func1/pci_epf_vntb.0/num_mws
  $ echo 0xE0000 > functions/pci_epf_vntb/func1/pci_epf_vntb.0/mw1
  $ echo 0x20000 > functions/pci_epf_vntb/func1/pci_epf_vntb.0/mw2
  $ echo 0xE0000 > functions/pci_epf_vntb/func1/pci_epf_vntb.0/mw2_offset
  $ echo 2       > functions/pci_epf_vntb/func1/pci_epf_vntb.0/mw1_bar
  $ echo 2       > functions/pci_epf_vntb/func1/pci_epf_vntb.0/mw2_bar

Signed-off-by: Koichiro Den <den@...inux.co.jp>
---
 drivers/ntb/hw/epf/ntb_hw_epf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/ntb/hw/epf/ntb_hw_epf.c b/drivers/ntb/hw/epf/ntb_hw_epf.c
index efe540a8c734..18d27ba9b6f4 100644
--- a/drivers/ntb/hw/epf/ntb_hw_epf.c
+++ b/drivers/ntb/hw/epf/ntb_hw_epf.c
@@ -826,7 +826,7 @@ static const enum pci_barno rcar_barno[NTB_BAR_NUM] = {
 	[BAR_PEER_SPAD]	= BAR_0,
 	[BAR_DB]	= BAR_4,
 	[BAR_MW1]	= BAR_2,
-	[BAR_MW2]	= NO_BAR,
+	[BAR_MW2]	= BAR_2,
 	[BAR_MW3]	= NO_BAR,
 	[BAR_MW4]	= NO_BAR,
 };
-- 
2.51.0